Sections

July 6, 2018 -- The shutdown of shipments from a nuclear reactor in Australia that is a key part of the global supply network for the radioisotope molybdenum-99 (Mo-99) is causing consternation in the nuclear medicine community, particularly in the Asia-Pacific region.

The Australian Nuclear Science and Technology Organization (ANSTO) announced on June 27 that it had temporarily suspended production of technetium-99m generators due to mechanical problems at the site of the Open Pool Australian Lightwater (OPAL) reactor in Lucas Heights, outside of Sydney, according to an article in the Guardian. As of July 4, production was still suspended.

The generators contain molybdenum-99 and are sent to nuclear medicine facilities at hospitals and imaging centers. The Mo-99 decays into techentium-99m inside the generator and can then be used at imaging sites for a variety of studies, including nuclear cardiology.

The OPAL reactor produces about 10,000 generators a week, and in addition to supplying Australia it also ships generators to New Zealand and other facilities in the Asia-Pacific region. The interruption has forced Australian authorities to implement plans to receive backup supplies of generators from other countries, according to the Guardian.

Australia usually imports backup supplies of technetium-99m generators from South Africa, but a reactor there has been shut down for maintenance, according to the article. Australia received an initial wave of generators from Lantheus Medical Imaging in the U.S., equaling about 39% of what would be used in a week, but a second shipment of 60 generators was delayed and wasn't expected to arrive by plane until July 5, to be distributed to healthcare facilities on July 6, according to a statement by ANSTO.

A third batch of generators is being produced in the U.S. and is scheduled for delivery the week of July 9, the statement noted.

Technetium-99m is being rationed within the country, and patients in rural areas and regional locations are having to fly to major cities to undergo nuclear cardiology tests, the Guardian noted.

The OPAL reactor is part of a fragile network of isotope suppliers around the world in which essentially four sources handle the world's entire Mo-99 supply from fewer than a dozen nuclear reactors. The nuclear medicine community hopes to develop a network of alternative sources for Mo-99 that doesn't rely on reactors and, thus, offers a more stable supply, but it's taking time to get these sources up and running.

The mechanical problem concerns a part called a transfer conveyor, and it does not affect the operation of the OPAL reactor itself or the production of other nuclear medicine products, ANSTO noted.